update-spans-metric

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate write operation (readOnlyHint=false) and open world (openWorldHint=true). The description adds the specific fields that can be updated, offering some behavioral context, but does not disclose error handling, idempotency, or side effects implied by openWorldHint.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single concise sentence with no wasted words, front-loading the verb and resource. It efficiently conveys the core action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a tool with 4 parameters, no output schema, and annotations provided, the description adequately states the action. However, it does not address the openWorldHint implications or mention that percentile updates are only for distribution metrics (though covered in the parameter description). It is sufficient but not enhanced.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with informative parameter descriptions. The tool description summarizes the parameter categories (filter, group-by, percentile) but adds no new meaning beyond what the schema already provides. Baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'Update' and the resource 'span-based metric', and lists the specific updatable settings (filter, group-by, percentile). This distinguishes it from sibling tools like create-spans-metric, delete-spans-metric, and get-spans-metric.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It does not mention when to use create-spans-metric for new metrics or delete-spans-metric for removal, nor does it specify prerequisites or context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.